Yamaha XT400 1985 HELP

[Rik]

Mate of mine, who is completely computer illiterate, is having electrical probs with his XT. I believe it to be the CDI unit which is faulty. Was hoping someone out there would have a wiring diagram they could scan and send, or failing that, I could set up a dialouge with someone who has knowledge on this model.

Cheers

Rik

[cheese]

From what I know if I CDI is rooted, you need to swap it. They are a sealed unit that can't be fixed. IN saying that the wiring diagram my manual has looks pretty simple.

Anyway....

I'd take the coil out and get it tested as that is a easy test that would show that part up pretty quickly. Then check that the mag coils are ok. It would be as simple as the HT lead. Then I'd also take to all the connectors with a Tooth brush and some IPA adn clean all teh contacts. Or use contact cleaner.

Does it run at all?

[Wellyman]

From what I know if I CDI is rooted, you need to swap it. They are a sealed unit that can't be fixed. IN saying that the wiring diagram my manual has looks pretty simple.

Anyway....

I'd take the coil out and get it tested as that is a easy test that would show that part up pretty quickly. Then check that the mag coils are ok. It would be as simple as the HT lead. Then I'd also take to all the connectors with a Tooth brush and some IPA adn clean all teh contacts. Or use contact cleaner.

Does it run at all?
Cheesee is right here. check the coil, a CDI is rooted if it is acting wonky so you will have to find a used one from a bike wrecker as Yamaha will charge you millions for it.
WM

[XTC]

Or if you find your CDI is fcuked you could get one of these.....
http://www.trademe.co.nz/Trade-Me-Motors/Motorbikes/Parts-accessories/Other/auction-55640820.htm

[Rik]

Cheers for the help fellas, Pete will be checking the mag coils so maybe that will cure the prob. Nb the bike was going, if eratically, till Pete decided to connect all the lights and indicators. Since then NO GO.
Cheese; would appreciate if you could scan your wiring diagram and email it to me. The library here has no manual for this model, which makes for hit and miss repairs,eh.

Thanks again
Cheers, Rik

[cheese]

Mate my bike is a RM 250 two smoke, probably completely different.

Is there a spark? has he played with the timing?

I had an old IT 175 and that ran like shit, I thought it was the CDI, turned out to be one loose wire!

[Rik]

'sfar as I know there is no spark, and yep befor it died he was forever playing with the timing, also the carb. Oh well heres hoping he can figure it out or he may just have to junk it. nb only cost him a couple a hundred slides!!
Thanks for trying any way

Cheers

Rik

[Wellyman]

'sfar as I know there is no spark, and yep befor it died he was forever playing with the timing, also the carb. Oh well heres hoping he can figure it out or he may just have to junk it. nb only cost him a couple a hundred slides!!
Thanks for trying any way

Cheers

Rik

When was the last time the motor was checked? has he got a service record for it? I would get the motor open and check some of the internals, maybe piston is seized etc. just a thought.WM

[Motu]

Sounds like there has been some irational diagnosis and clutching at straws - back to basics and take a methodical approach.